<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no"/>
    <title>smilevue</title>
  </head>
  <body>
    <div id="app"></div>
    <!-- built files will be auto injected -->
  </body>
<script>
  //得到手机屏幕的宽度
  let htmlWidth = document.documentElement.clientWidth || document.body.clientWidth;
  //得到html的Dom元素
  let htmlDom = document.getElementsByTagName('html')[0];
  //设置根元素字体大小
  htmlDom.style.fontSize= htmlWidth/20 + 'px';
  if(htmlWidth>=750){htmlWidth=750}
</script>
</html>
